My thoughts on Gestated E6 would prompt a munchkin based argument with you, far easier for you to compentate (sp) what I could mean than for you to jump the gun and twist my words.
Why did you bring up gestalt E6 at all? It has nothing to do with the topic. I doubt anyone particularly was interested in your opinion on a style of play you've never actually played that has nothing to do with the present topic.
KoK is a supplement, not a replacement. KoK based games have a Cleric/Druid/Sorcerer/Wizard, unless you're point was none of it's Base Classes offer full Spellcasting.
Eberron's a suppliment in the same way (they're both settings) and it still brings in the Artificer. Faerun too, and that has the Incantrix. Heroes of Horror is a supplement (though not a setting), and it still brings in the Archivist. My point was that there's less seriously broken stuff in KoK than there is in core or Eberron (or Faerun).
Maybe, the main pdf is on the desktop and I've never bothered with it's splat to know if you are incorrect in that assessment. But never the less KoK pops up on here with some horrendously broken crap. For instance, a cl/hour +10 Deflection 1st level Spell. If you can't see what's wrong with it, well that's another song for another day. Also, there is a lot wrong with Core yes, but Core invented D&D as you know it. And over 90 supplements and 20+ adventures you're bound to have oddities pop out. But a 3rd party supplement had time, had feedback, had resources, and had comments to do far far far better. Despite this, KoK breaks the bank. Horrendously. And because of that, it'll never even live up to your comments on being comparable to the Incantatrix. It's worse.
Seriously, if all you knew about Eberron was the Artificer, you'd think Eberron was nothing but broken too. But having gone through all the most powerful spells in existence for a high powered game where I played as an Archivist, I find I only picked out 3 from KoK (Mule's Enlightenment, Holy Defense, A Moment Ago). There's also Unholy Defense but that's just a clone of Holy Defense for evil people... and you know these two spells only give +10AC at very high level, right? By comparison, I picked out over 200 spells total. Spells like Extract Gift (Spell stitch it on a Zombie Dragon or similar while buffing Wisdom on that creature and make yourself count as a demon, and you can give out free buffs to anyone you want and then see out their eyes and ears), Genesis (need I say it?), Planar Binding (endless wishes!), Unseen Crafter (endless production of anything from a level 2 spell!), Black Sand (Endless all day healing for anyone healed by undead as a level 2 spell and you only have to cast it once!), Call Faithful Servants (get angel minions for a year with a single casting), Ghoul Glyph (no save paralysis on a level 2 spell, and Factotums cast it as a standard action), Animate Dread Warrior (get minions with class levels), Guidance of the Avatar (3rd level spell that gives +20 to a skill check), Favorable Sacrifice (3rd level spell that gives DR 20/Magic, SR 10+CL, Resist all Energy 20, for hour/lvl if you can avoid the costly material component) and so on are found all over the books, not in KoK.
KoK is an underpowered setting with just a few gems in it. And are you really claiming that +10AC at 10th level (with drawbacks of reduced concealment and hide) is horribly overpowered? Since when has AC at high level been horribly powerful? Oh no, someone got some AC! Mule's Enlightenment is overpowered (but much higher level, and the skill boost is excused by it being a 3.0 spell) but +10 AC and you glow at 10th level? Seriously? Favorable Sacrifice blows it away, and that's in Spell Compendium.
I mean, I have my criticisms of KoK, certainly. I find the world a bit boring. Most of the PrCs are really weak, to the point of being completely pointless. A lot feels uninspired. And other than a few really cool and powerful spells, most of it just isn't that interesting. But stupidly overpowered? Please. Eberron blows it away, and Faerun is even worse. Rokugan too, for that matter. So how exactly does it break the bank? With some AC that melees can actually use? Do you think a spell that gives more AC than most is worse than, I dunno, True Creation or Stone Metamorphosis or Animate Dread Warrior? I can break the heck out of the game with Incantrix. Can you break the heck out of the game by buffing a pet Fighter with some AC?
Though I did read it over and find the stupid spell is personal range only. So, not as good as previously assumed.
JaronK